Something peculiar has been going on in science for the past 100 years or so. Many researchers are unaware of it, and others won’t admit it even to their own colleagues. But there is strangeness in the air.
What has happened is that biologists, who once postulated a privileged role for the human mind in nature’s hierarchy, have been moving relentlessly toward the hard-core materialism that characterized nineteenth-century physics. At the same time, physicists, faced with compelling experimental evidence, have been moving away from strictly mechanical models of the universe to a view that sees the mind as playing an integral role in all physical events. It is as if the two disciplines were on two fast-moving trains, going in opposite directions and not noticing what is happening across the tracks.
This role reversal by biologists and physicists has left the contemporary psychologist in an ambivalent position. From the perspective of biology, the psychologist studies phenomena that are far removed from the core of certainty, that is, the submicroscopic world of atoms and molecules. From the perspective of physics, the psychologist deals with “the mind,” and undefined primitive that seems at once essential and impenetrable. Clearly both views embody some measure of truth – and a resolution of the problem is essential to deepening and extending the foundations of behavioural science.
The study of life at all levels, from the social to molecular behaviour, has
“Rediscovered the Mind,” by Harold J. Morowitz. From Psychology Today, August 1980. Reprinted by permission of the author.
In modern times relied on reductionism as the chief explanatory concept. This approach to knowledge tries to comprehend one level of scientific phenomena in terms of concepts at a lower and presumably more fundamental level. In chemistry, large-scale reactions are accounted for by examining the behaviour of molecules. Similarly, physiologists study the activity of living cells in terms of processes carried out by organelles and other subcellular entities. An din geology, the formations and properties of minerals are described using the features of the constituent crystals. The essence of these cases is seeking explanation in underlying structures and activities.
Reductionism at the psychological level is exemplified by the viewpoint in Carl Sagan’s best-selling book The Dragons of Eden. He writes: “My fundamental premise about the brain is that all its workings – what we sometimes call ´´ `mind´ – are a consequence of its anatomy and physiology and nothing more.” As a further demonstration of this trend of thought, we note that Sagan’s glossary does not contain the words mind, consciousness, perception, awareness, or thought, but rather deals with entries such as synapse, lobotomy, proteins, and electrodes.
Such attempts to reduce human behaviour to its biological basis have a long history, beginning with early Darwinians and their contemporaries working in physiological psychology. Before the nineteenth-century, the mind-body duality, which was central to Descartes’ philosophy, had tended to place the human mind outside the domain of biology. Then the stress that the evolutionists placed on our “apeness” made us subject to biological study by methods appropriate to nonhuman primates and, by extension, to other animals. The Pavlovian school reinforced that theme, and it became a cornerstone of many behavioural theories. While
No general agreement has emerged among psychologists as to how far reductionism should be carried, most will readily concede that our actions have hormonal, neurological, and physiological components. Although Sagan’s premise lies within a general tradition in psychology, it is radical in aiming at complete explanation in terms of the underlying level. This goal I take to be the thrust of his phrase “and nothing more.”
At the time various schools of psychology were attempting to reduce their science to biology, other life scientists were also looking for more basic levels of explanation. Their outlook can be seen in the writings of a popular spokesman of molecular biology, Francis Crick. In his book, Of Molecules and Men, a contemporary attack on vitalism – the doctrine that biology needs to be explained in terms of life forces lying outside the domain of physics – Crick states: “The ultimate aim of the modern movement in biology is in fact to explain all biology in terms of physics and chemistry.” He goes on to say that by physics and chemistry he refers to the atomic level, where are knowledge is secure. By use of the italicized all, he expresses the position of radical reductionism that has been the dominant viewpoint among an entire generation of biochemists and molecular biologists.
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If we now combine psychological and biological reductionism and assume they are going to overlap, we end up with a sequence of explanation going from mind to anatomy and physiology, to cell physiology, to molecular biology, to atomic physics. All this knowledge is assumed to rest on a firm bedrock of understanding the laws of quantum physics, the newest and most complete theory of atomic structures and processes. Within this context, psychology becomes a branch of physics, a result that may cause some unease among both groups of professionals.
This attempt to explain everything about human beings in terms of the first principles of physical science is not a new idea and had reached a definitive position in the views of the mid-nineteenth-century European physiologists. A representative of that school, Emil Du Bois-Reymond, set forth his extreme opinions in the introduction to an 1848 book on animal electricity. He wrote that “if our methods only were sufficient, an analytical mechanics (Newtonian physics) of general life processes would be possible and fundamentally would reach even to the problem of the freedom of the will.”
There is a certain hubris in the words of these early savants that was picked up by Thomas Huxley and his colleagues in their defense of Darwinism and, even today, echoes in the theories of modern reduction-
ists who would move from the mind to the first principles of atomic physics. It is most clearly seen at present in the writings of the sociobiologists, whose arguments animate the contemporary intellectual scene. In any case, Du Bois-Reymond’s views are consistent with modern radical reductionists, except that quantum mechanics has how replaced Newtonian mechanics as the underlying discipline.
During the period in which psychologists and biologists were steadily moving toward reducing their disciplines to the physical sciences, they were largely unaware of perspectives emerging from physics that cast an entirely new light on their understanding. Toward the close of the last century, physics presented a very ordered picture of the world, in which events unfolded in characteristic, regular ways, following Newton’s equations in mechanics and Maxwell’s in electricity. These processes moved inexorably, independent of the scientist, who was simply a spectator. Many physicists considered their subject as essentially complete.
Starting with the introduction of the theory of relativity by Albert Einstein in 1905, this neat picture was unceremoniously upset. The new theory postulated that observers in different systems moving with respect to each other, would perceive the world differently. The observer thus became involved in establishing physical reality. Te scientist was losing the spectator’s role and becoming an active participant in the system under study.
With the development of quantum mechanics, the role of the observer became an even more central pat of physical theory, an essential component in defining an event. The mind of the observer emerged as a necessary element in the structure of the theory. The implications of the developing paradigm greatly surprised early quantum physicists and led them to study epistemology and the philosophy of science. Never
Before in scientific history, to my knowledge, had all the leading contributors produced books and papers expounding the philosophical and humanistic meaning of their results.
Werner Heisenberg, one of the founders of the new physics, became deeply involved in the issues of philosophy and humanism. In Philosophical Problems of Quantum Physics, he wrote of physicists having to renounce thoughts of an objective time scale common to all observers, and of events in time and space that are independent of our ability to observe them. Heisenberg stressed that the laws of nature are no longer dealt with elementary particles, but with our knowledge of these particles – that is, with the contents of our minds. Erwin Schrödinger, the man who formulated the fundamental equation of quantum mathematics, wrote an extraordinary little book in 1958 called Mind and Matter. In this series of essays, he moved from the results of the new physics to a rather mystical view of the universe that he identified with the “perennial philosophy” of Aldous Huxley. Schrödinger was the first of the quantum theoreticians to express sympathy with the Upanishads and eastern philosophical thought. A growing body of literature now embodies this perspective, including two popular works, The Tao of Physics by Fritjof Capra and the Dancing Wu Li masters by Gary Zukav.
The problem faced by quantum theorists can best be seen in the famous paradox. “Who killed Schrödinger’s cat?” In a hypothetical formulation, a kitten is put in a closed box with a jar of poison and a triphammer poised to smash the jar. The hammer is activated by a counter that records random events, such as radioactive decay. The experiment lasts just long enough for there to be a probability of one-half that the hammer will be released. Quantum mechanics represents the system mathematically by the sum of a live-cat and a dead-cat function, each with a probability of one-half. The question is whether the act of looking (the measurement) kills or saves the cat, since before the experimenter looks in the box both solutions are equally likely.
This lighthearted example reflects a deep conceptual difficulty. In more formal terms, a complex system can only be described by using a probability distribution that relates the possible outcomes of an experiment. In order to decide among the various alternatives, a measurement is required. This measurement is what constitutes an event, as distinguished from the probability which is a mathematical abstraction. However, the only simple and consistent description physicists were able to assign to a measurement involved an observer’s becoming aware of the result. Thus the physical event and the content of the human mind were inseparable. This linkage forced many researchers to seriously consider consciousness as an integral part of the structure of physics. Such inter-
pretations moved science toward the idealist as contrasted with the realist conception of philosophy.
The views of a large number of contemporary physical scientists are summed up in the essay “Remarks on the Mind-Body Question” written by Nobel laureate Eugene Wigner. Wigner begins by pointing out that most physical scientists have returned to the recognition that thought – meaning the mind – is primary. He goes on to state: “It was not possible to formulate the laws of quantum physics in a fully consistent way without reference to the consciousness.” And he concludes by noting how remarkable it is that the scientific study of the world led to the content of consciousness as an ultimate reality.
A further development in yet another field of physics reinforces Wigner’s viewpoint. The introduction of information theory and its applications to thermodynamics has led to the conclusion that entropy, a basic concept of that science, is a measure of the observer’s ignorance of the atomic details of the system. When we measure the pressure, volume, and temperature of an object, we have a residual lack of knowledge of the exact position and velocity of the component atoms and molecules. The numerical value of the amount of information we are missing is proportional to the entropy. In earlier thermodynamics, entropy had represented, in an engineering sense, the energy of the system unavailable to perform external work. In the modern view, the human mind enters once again, and entropy relates not just to the state of the system but to our knowledge of that state.
The founders of modern atomic theory did not start out to impose a “mentalist” picture on the world. Rather, they began with the opposite point of view and were forced to the present-day position in order to explain experimental results.
We are now in a position to integrate the perspectives of three large fields: psychology, biology and physics. By combining the positions of Sagan, Crick, and Wigner as spokesmen for the various outlooks, we get a picture of the whole that is quite unexpected.
First, the human mind, including consciousness and reflective thought, can be explained by activities of the central nervous system, which, in turn, can be reduced to the biological structure and function of that physiological system. Second, biological phenomena at all levels, can be totally understood in terms of atomic physics, that is, through the action and interaction of the component atoms of carbon, nitrogen, oxygen, and so forth. Third, and last, atomic physics, which is now understood most fully by means of quantum mechanics, must be formulated with the mind as a primitive component of the system.
We have thus, in separate
Circle – from the mind, back to the mind. The results of this chain of reasoning will probably lead more aid and comfort to Eastern mystics than to neurophysiologists and molecular biologists; nevertheless, the closed loop follows from a straightforward combination of the explanatory processes of recognized experts in the three separate sciences. Since individuals seldom work with more than one of these paradigms, the general problem has received little attention.
If we reject this epistemological circularity, we are left with two opposing camps: a physics with a claim to completeness because it describes all of nature, and a psychology that is all-embracing because it deals with the mind, our only source of knowledge of the world. Given the problems in both of these views, it is perhaps well to return to the circle and give it more sympathetic consideration. If it deprives us of firm absolutes, at least it encompasses the mind-body problem and provides a framework within which individual disciplines can communicate. The closing of the circle provides the best possible approach for psychological theorists.
The strictly reductionist approach to human behaviour so characteristic of sociobiology also runs into trouble on more narrowly biological grounds. For it includes an assumption of continuity in evolution from early mammals to man, which implies that the mind, or consciousness, was not a radical departure. Such an assumption is hardly justified when one considers the dramatic instances of discontinuity in evolution. The origin of the universe itself, the “big bang,” is a cosmic example of a discontinuity. Te beginning of life, while less cataclysmic, is certainly another example.
The encoding of information in genetic molecules introduced the possibility of profound disturbances in the laws that governed the universe. Before the coming of genetic life, for example, fluctuations in temperature or noise were averaged out, giving rise to precise laws of planetary evolution. Afterward however, a single molecular event at the level of thermal noise could lead to macroscopic consequences. For if the event were a mutation in a self-replicating system, then the entire course of biological evolution could be altered. A single molecular event could kill a whale by inducing a cancer or destroy an ecosystem by generating a virulent virus that attacks a key species in that system. The origin of life does not abrogate the underlying laws of physics, but it adds a new feature: large scale consequences of molecular events. This rule change makes evolutionary history indeterminate and so constitutes a clear-cut discontinuity.
A number of contemporary biologists and psychologists believe that the origin of reflective thought that occurred during primate evolution is also a discontinuity tat has changed the rules. Again, the new situation does not abrogate the underlying biological laws, but it adds a feature that necessitates novel ways of thinking about the problem. The evolutionary biologist Lawrence B. Slobodkin has identified the new feature as an introspective self-image. This property he asserts, alters the response to evolutionary problems and makes it impossible to assign major historical events to cause inherent in biological evolutionary laws. Slobodkin is claiming that the rules have changed and man cannot be understood by laws applicable to other mammals whose brains have a very similar physiology.
This emergent feature of man has, in one form or another, been discussed by numerous anthropologists, psychologists , and biologists. It is part of the empirical data that cannot be shelved just to preserve reductionist purity. The discontinuity needs to be thoroughly studied and evaluated, but first it needs to be recognized. Primates are very different from other animals, and human beings are very different from other primates.
We now understand the troublesome features in a forceful commitment to uncritical reductionism as a solution to the problem of the mind. We have discussed the weaknesses of that position. In addition to being weak, it is a dangerous view, since the way we respond to our fellow human beings is dependent on the way we conceptualize them in our theoretical formulations. If we envision our fellows solely as animals or machines, we drain our interactions of humanistic richness. If we seek our behavioural norms in the study of animal societies, we ignore those
uniquely human features that so enrich our lives. Radical reductionism offers very little in the area of moral imperatives. Further, it presents the wrong glossary of terms for a humanistic pursuit.
The scientific community has made notable progress in understanding the brain, and I share the enthusiasm for neurobiology that characterizes modern-day research. Nevertheless, we should be reluctant to let that élan generate statements that go beyond science and lock us into philosophical positions that impoverish our humanity by denying the most intriguing aspect of our species. To underrate the significance of the appearance and character of reflective thought is a high price to pay in order to honour the liberation of science from theology by our reductionist predecessors several generations back. The human psyche is part of the observed data of science. We can retain it and still be good empirical biologists and psychologists.
Harold J. Morowitz
“The garden of Forking Paths” is a picture, incomplete yet not false, of the universe as Ts´ui Pên conceived it to be. Differing from Newton and Schopenhauer.. (he) did not think of time as absolute and uniform . He believed in an infinite series of times, in a dizzily growing, ever spreading network of diverging, converging and parallel times. This web of time – the strands of which approach one another, bifurcate, intersect, or ignore each other through the centuries – embraces every possibility. We do not exist in most of them. In some you exist and not I, while in others I do, and you do not, and yet in others both of us exist. In this one, in which chance has favoured me, you have come to my gate. In another, you, crossing the garden have found me dead. In yet another, I say these very same words, but am an error, a phantom.
Jorge Luis Borges
“The garden of Forking Paths”
Actualities seem to float in a wider see of possibilities from out of which they were chosen; and somewhere, indeterminism says, such possibilities exist, and form part of the truth.
-- William James
It is an attractive notion that the mysteries of quantum physics and the mysteries of consciousness are somehow one. The epistemological loop that Morowitz describes has just about the proper amounts of hard sci-
ence, beauty, weirdness, and mysticism to “sound right.” However, it is an idea that in many ways opposes an important them of this book, which is that nonquantum-mechanical computational models of mind (all that goes along with mind) are possible in principle. Bur right or wrong – and it is too early to say – the ideas that Morowitz presents are worth thinking about, for there is a certainly no question that the problem of the interaction of subjective and objective viewpoints is a conceptual difficulty at the heart of quantum mechanics. In particular, quantum mechanics as it is usually cast accords a privileged causal status to certain systems known as “observers” without spelling out whether consciousness is a necessary ingredient of observer status). To clarify this point we must present a quick overview of the “measurement problem” in quantum mechanics, and we will invoke the metaphor of the “quantum wave faucet” for that purpose.
Imagine a faucet with two knobs – hot and cold – each of which you can twist continuously. Water comes streaming out of the faucet, but there is a strange property to this system. The water is always totally hot or totally cold – no in-between. These are called the “two temperature eigenstates” of the water. The only way you can tell which eigenstate the water is in is by sticking your hand in and feeling it. Actually, in orthodox quantum mechanics it is trickier than that. It is the act of putting your hand under the water that throws the water into one or the other eigenstate. Up until that very instant, the water is said to have be in a superposition of states (or more accurately, a superposition of eigenstates)
Depending on the setting of the knobs, the likely hood of cold water will vary. Of course, if you turn on only the “H” tap, then you’ll get hot water always, and if you turn on only “C,” then you’ll get cold water for sure. If you open both valves, however, you’ll create a superposition of states. By trying it over and over again with one setting, you can measure the probability tat you’ll get cold water with that setting. After that, you can change the setting and try again. There will be some crossover point where hot and cold are equally likely. It will be like flipping a coin. (This quantum water faucet is sadly reminiscent of many a bathroom shower.) Eventually you can build up enough data to draw a graph of the probability of cold water as a function of the knobs’ settings.
Quantum phenomena are like this. Physicist can twiddle knobs and put systems into superpositions of states analogous to our hot-cold superpositions. As long as no measurement is made of the system, the physicists cannot know which eigenstate the system I sin. Indeed it can
Be shown that in a very fundamental sense the system itself does not “know” which eigenstate it is in, and that it decides – at random – only at the moment the observer’s hand is put in to “test the water,” so to speak. The system, up till the moment of observation, acts as if it were not in an eigenstate. For all practical purposes, for all theoretical purposes – in fact for all purposes—the system is not in an eigenstate.
You can imagine doing a lot of experiments on the wate coming out of a quantum water faucet to determine if its is actually hot or actually cold without sticking your hand in (we’re of course assuming that there are no telltale clues such as steam). For example, run your washing machine on the water from the faucet. Still, you won’t know if your wool sweater has shrunk or not until the moment you open the washing machine (a measurement made by a conscious observer). Make some tea with water from the faucet. Still, you won’t know if you’ve got iced tea or not, until you taste it (interaction with a conscious observer again). Attach a recording thermometer just under the water faucet. Until you yourself see the reading on the thermometer or the ink marks on its record, you can’t know the temperature. You can’t be any surer that the ink is on the paper than you are that the water has a definite temperature. The critical point here is that the sweater and the tea and the thermometer, not having conscious-observer status themselves, have to play along with the gag and, just as the water did, enter their own superpositions of states – shrunk and nonshrunk, iced-tea-and-hot-tea, ink-high-and ink-low.
This may sound as if it has nothing to do with physics per se but merely with ancient philosophical conundrums such as “Does a tree in a forest make a noise when it falls if there’s no one there to hear it?” But the quantum-mechanical twist on such riddles is that there are observation consequences that are diametrically opposite to the consequences that would occur if a seemingly mixed state were in reality always a true eigenstate, merely hiding its identity from observers until the moment of measurement. In crude terms, a stream of maybe-hot-maybe-cold water would act differently from a stream of water that is actually hot or actually cold, because the two alternatives “interfere” with each other in the sense of overlapping waves (as when part of a speedboat’s wake momentarily cancels another part reflected of a jetty, or when a skipped rock’s successive bounces send out ripples that crisscross and create shimmering patterns on a still lake surface). It turns out that such interference effects are only statistical, so the effect would become manifest only after a large number of sweater-washings or tea-makings. Interested readers should consult the beautiful exposition of this difference in The character of Physical law by Richard Feynman.
The plight of Schrödinger’s cat carries this idea further – that even a cat could be in a quantum-mechanical superposition of states until a human observer intervened. One might object, and say, “Wait a minute! Isn’t a live cat as much of a conscious observer as a human being is?” Probably it is – but notice that this cat is possibly a dead cat, which
is certainly not a conscious observer. In effect, we have created, in Schrödinger’s cat, a superposition of two eigenstates one of which has observer status, the other of which lacks it! Now what shall we do? The situation is reminiscent of a Zen riddle (recounted in Zen Flesh, Zen Bones by Paul Repx) posed by the master Kyögen:
Zen is like a man hanging in a tree by his teeth over a precipice. His hands grasp no branch, his feet rest on no limb, and under the tree another person asks him: “Why did Bodhidharma come to China from India?” if the man in the tree does not answer, he fails; and if he does answer, he falls and loses his life. Now what shall he do?
To many physicists the distinction between systems with observer status and those without has seemed artificial, even repugnant. Moreover, the idea that an observer’s intervention causes a “collapse of the wave function” -- a sudden jump into one randomly chosen pure eigenstate – introduces caprice into the ultimate laws of nature. “God does not play dice” (“Der Herrgott wurfelt nicht” was Einstein’s lifelong belief.
A radical attempt to save both continuity and determinism in quantum mechanics is known as the “many-worlds interpretation” of quantum mechanics, first proposed in 1957 by Hugh Everett III. According
to this very bizarre theory, no system ever jumps discontinuously into an eigenstate. What happens is that the superposition evolves smoothly with its various branches unfolding in parallel. Whenever necessary, the state sprouts further branches that carry the various new alternatives. For instance, there are two branches in the case of Schrödinger’s cat, and they both develop in parallel. “Well, what happens to the cat? Does it feel itself to be alive, or dead?” one must wonder. Everett would answer, “It depends which branch you look at. On one branch it feels itself alive, and on the other there’s no cat to feel anything.” With intuition beginning to rebel, one then asks, “Well, what about a few moments before the cat on the fatal branch died? How did the cat feel then? Surely the cat can’t feel two ways at once! Which of the two branches contains the genuine cat?
The problem becomes even more intense as you realize the implications of this theory as applied to you, here and now. For every quantum mechanical branch in your life (and there have been billions upon billions), you have split into two or more yous, riding along parallel but disconnected branches of one gigantic “universal wave function.” At the critical spot in his article where this difficulty arises, Everett calmly inserts the following footnote:
At this point we encounter a language difficulty. Whereas before the observation we had a single observer state, afterwards there were a number of different sates for the observer, all occurring in a superposition. Each of these separate states is a state for an observer, so that we can speak of the different observers described by different states. On the other hand, the same physical system is involved, and from this viewpoint it is the same observer, which is in different states for different elements of the superposition (i.e., had had different experiences in the separate elements of the superposition). In this situation we shall use the singular when we wish to emphasize that a single physical system is involved, and the plural when we wish to emphasize the different experiences for the separate elements of the superposition (E.g., “The observer performs an observation of the quantity A, after which each of the observers of the resulting superposition has perceived an eigenvalue.”)
All said with a poker face. The problem of how it feels subjectively is not treated; it is just swept under the rug. It is probably considered meaningless.
And yet, one simply has to wonder, “Why, then, do I feel myself to be in just one world?” Well, according to Everett’s view, you don’t – you feel all the alternative simultaneously, it’s just this you going down this branch who doesn’t experience all the alternatives. This is completely shocking. The vivid quotes with which we opened our reflection come
Back and penetrate deeply. The ultimate question is this: “Why is this me in this branch, then? What makes me – I mean this me – feel itself – I mean myself – unsplit?”
The sun is setting one evening over the ocean. You and a group of friends are standing at various points along the wet sand. As the water laps at your feet, you silently watch the red globe drop nearer and nearer to the horizon. As you watch, somewhat mesmerized, you notice how the sun’s reflection on the wave crests forms a straight line composed of thousands of momentary orange-red glints – a straight line pointing right at you” “How lucky that I am the one who happens to be lined up exactly with that line”” you think to yourself. “Too bad not all of us can stand here and experience this perfect unity with the sun.” And at the same moment, each of your friends is having precisely the same thought . . or is it the same?
Such musings are at the heart of the “soul-searching question.” Why is this soul in this body? (Or on this branch of the universal wave function?” Why, when there are so many possibilities, did this mind get attached to this body? Why can’t my “I-ness” belong to some other body? It is obviously circular and unsatisfying to say something like “You are in that body because that was the one made by your parents.” But why were they my parents, and not someone else? Who would have been my parents if I had been born in Hungary? What would I have been like if I had been someone else? Or if someone else had been me? Or – am I someone else? Am I everyone else? Is there only one universal consciousness? Is it an illusion to feel oneself as separate, as an individual? It is rather eerie to find these bizarre themes reproduced at the core of what is supposedly our stablest and least erratic science.
And yet in a way it is not so surprising. There is a clear connection between the imaginary worlds in our minds and the alternate worlds evolving in parallel with the one we experience. The proverbial young man picking apart the daisy and muttering, “She loves me, she loves me not, she loves me, she loves me not is clearly maintaining in his mind (at least) two different worlds based on two different models for his beloved. Or would it be more accurate to say that there is one mental model of his beloved that is in a mental analogue of a quantum-mechanical superposition of states?
And when a novelist simultaneously entertains a number of possible ways of extending a story, are the characters not, so to speak metaphorically, in a mental superposition of states? If the novel never gets set to paper, perhaps the split characters can continue to evolve their multiple stories in their author’s brain. Furthermore, it would even seem strange to ask
which story is the genuine version. All the worlds are equally genuine.
And in like manner, there is a world -- a branch of the universal wave function – in which you didn’t make that stupid mistake you now regret so much. Aren’t you jealous? But how can you be jealous of yourself? Besides which, there’s another world in which you made yet stupider mistakes, and are jealous of this very you, here and now in this world!
Perhaps one way to think of the universal wave function is as the mind – or brain, if you prefer – of the great novelist in the sky, God, in which all possible branches are being simultaneously entertained. We would be mere subsystems of God’s brain, and these versions of us are no more privileged or authentic tan our galaxy is the only genuine galaxy. God’s brain, conceived in this way, evolves smoothly and deterministically, as Einstein always maintained. The physicist Paul Davies, writing on just this topic in his recent book Other Worlds, says: “our consciousness weaves a route at random along the ever-branching evolutionary pathway of the cosmos, so it is we, rather than God, who are playing dice.”
Yet this leaves unanswered the most fundamental riddle that each of us must ask: “Why is my unitary feeling of myself propagating down this random branch rather than down some other? What law underlies the random choices that pick out the branch I feel myself tracing out? Why doesn’t my felling of myself go along with the other me’s as they split off, following other routes? What attaches me-ness to the viewpoint of this body, evolving down this branch of the universe at this moment in time?”
the question is so basic that it almost seems to defy clear formulation in words. And the answer does not seem to be forthcoming from quantum mechanics. In fact, this is exactly the collapse of the wave function reappearing at the far end of the rug as it was shoved under by Everett. It turns it into a problem of personal identity, no less perplexing than the original problem it replaces.
One can fall even more deeply into the pit of paradox when one realizes that there are branches of this one gigantically branching universal wave function on which there is no evidence for quantum mechanics whatsoever, branches on which there is no Everett or many-worlds interpretation of quantum mechanics. There are branches on which this entire Reflection got written exactly as you see it here, except that ended with a different flutzpah.
Something peculiar has been going on in science for the past 100 years or so. Many researchers are unaware of it, and others won’t admit it even to their own colleagues. But there is strangeness in the air.